Thermodynamic Investigation of Recuperative Organic Rankine Cycles for Waste Heat Recovery
Advanced Materials and Engineering: Characterization, Modeling, And Emerging Applications, Assoc. Prof. Dr. M. İlhan, Editör, Bzt Turan Publishing House Delaware, USA, , Delaware, ss.97-112, 2026
- Yayın Türü: Kitapta Bölüm / Araştırma Kitabı
- Basım Tarihi: 2026
- Doi Numarası: 10.30546/19023.978-9952-610-77-5.2026.100.1134
- Yayınevi: Bzt Turan Publishing House Delaware, USA,
- Basıldığı Şehir: Delaware
- Sayfa Sayıları: ss.97-112
- Editörler: Assoc. Prof. Dr. M. İlhan, Editör
- Van Yüzüncü Yıl Üniversitesi Adresli: Evet
Özet
Abstract
Research on waste heat recovery is increasing day by
day. This work evaluates a Recuperative Organic Rankine Cycle (RORC) system
utilized for electricity production from waste heat sources. A mathematical
model for the RORC was developed in Engineering Equation Solver (EES) to
optimize the power cycle's energy performance. Fourteen organic fluids suitable
for the operating temperatures were selected as candidates for the cycle.
Subsequently, a fluid analysis was conducted to identify the working fluids
that yielded the highest thermal efficiency. Among these candidates, three
organic fluids demonstrating high thermal efficiency and the highest
electricity generation values were selected based on operating conditions of
100°C for waste water inlet, 70°C for waste water outlet, and 32°C for the
condenser. 11
different organic working fluids were compared in detail through thermodynamic
simulations. When considering solely the system’s inherent thermodynamic
efficiency and hydraulic characteristics, R601 (n-pentane) demonstrated
superior performance compared to the other alternatives. Parametric evaluations
conducted with R601 yielded the highest first-law (thermal) efficiency, second-law
(exergy) efficiency, and net electric power output. Furthermore, this fluid
enabled the lowest mass flow rate requirement per unit of power generation. The
low mass flow rate allows for reductions in the heat transfer areas and
physical volumes of key heat exchange equipment, such as the evaporator,
condenser, and recuperator.
In the design of
modern energy systems, numerous criteria such as F-Gas regulations, low
environmental impact, environmental compliance, and operational safety are
vital to decision-making processes, extending beyond mere thermodynamic
efficiency. Due to the high flammability risk (Class A3) associated with the
R601 fluid, an alternative assessment was conducted within the framework of
environmental and safety standards. In this context, R1233zd(E)—a
next-generation hydrofluoroolefin (HFO) fluid characterized by an extremely low
Global Warming Potential (GWP < 1) and a high safety classification (A1) emerges
as a prominent candidate. It was determined that the efficiency and power
output values offered by R1233zd(E) are remarkably close to the theoretical
performance limits of R601. Consequently, R1233zd(E) was selected as the
optimal working fluid for the RORC system, as it ensures the lowest
environmental impact and the safest operating conditions without compromising
thermodynamic performance.